HYdroxide Salt Energy Storage Innovation

2026-07-22

Hyme is a Danish SME established in 2021, dedicated to revolutionizing large-scale energy storage by developing a Thermal Energy Storage (TES) system that stores energy in the form of high-temperature heat in molten salt. This solution can contribute to the decarbonization of energy-intensive industries (EII) and cogeneration utility companies – Combined Heat and Power plants (CHP), producing heat and electricity from a single energy source with a TES system that is affordable, Compact, Scalable, and Sustainable. The Hyme TES system is based on a known and +20 year-proven design from the concentrated solar power (CSP) industry, which allows us to work with established suppliers, uses mainly readily available system components, and avoids critical raw materials and harmful substances. While CSP traditionally relies on nitrates as the storage medium, HYME is pioneering the use of hydroxide salts, which have superior thermophysical properties and higher chemical stability at elevated temperatures, creating a novel TES relevant to many EIIs and CHP utility plants, hard-to-abate sectors where the penetration of green power is limited by the lack of solutions to control for the intermittent nature of renewable power. Sodium hydroxide’s high energy density brings additional advantages in terms of plant footprint (MWh/m2) and low total installed cost (TIC), and its excellent heat transfer properties enable it to be used effectively in high charge and discharge capacity settings. The TES system is built around our core technology – a patented method for adjusting oxoacidity and its implementation limiting and controlling the corrosion of hydroxide salts on structural materials in contact with the molten salt. Hyme was created as a spin-off from the Danish 4th generation nuclear startup Seaborg ApS. Our team comprises 35 FTEs (34% of women) representing a dozen nationalities.

Denmark

2025-10-15